Staff at the South Florida Museum are trying to figure out how a panel meant to prevent its animals from entering an access plumbing area became dislodged and allowed Snooty -- who was the world's oldest manatee in captivity -- to swim inside.

Snooty, having just celebrated its 69th birthday Saturday, July 22, was found dead a day later inside the restricted area at the Parker Manatee Aquarium.

A necropsy determined Snooty's cause of death to be drowning, said Jeff Rodgers, the South Florida Museum's director of education. Snooty, an 89-inch wide, 1,300-pound animal, had gotten stuck inside the area meant to access plumbing for the exhibit life support system.

"We do not know what happened to allow that panel to become dislodged," said Rodgers on Monday.

Daily inspections were performed on the habitat, and employees found nothing out of the ordinary at last check. Snooty had been the oldest known living manatee in captivity -- he was born in 1948 in Miami.

Museum staff earlier said their other rehab manatees – Randall, Gale and Baca – are all fine.

Education programs about manatees are in development even after Snooty's death, officials say.

The museum is set to reopen Tuesday; its normal operating hours are 10 a.m. to 5 p.m.

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